diff options
Diffstat (limited to 'vendor/rustix/src/imp/linux_raw/thread/syscalls.rs')
| -rw-r--r-- | vendor/rustix/src/imp/linux_raw/thread/syscalls.rs | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/vendor/rustix/src/imp/linux_raw/thread/syscalls.rs b/vendor/rustix/src/imp/linux_raw/thread/syscalls.rs new file mode 100644 index 000000000..600b4649d --- /dev/null +++ b/vendor/rustix/src/imp/linux_raw/thread/syscalls.rs @@ -0,0 +1,280 @@ +//! linux_raw syscalls supporting `rustix::thread`. +//! +//! # Safety +//! +//! See the `rustix::imp` module documentation for details. +#![allow(unsafe_code)] +#![allow(clippy::undocumented_unsafe_blocks)] + +use super::super::conv::{by_ref, c_int, c_uint, ret, ret_usize, ret_usize_infallible, zero}; +use crate::io; +use crate::process::{Pid, RawNonZeroPid}; +use crate::thread::{ClockId, FutexFlags, FutexOperation, NanosleepRelativeResult, Timespec}; +use core::mem::MaybeUninit; +use linux_raw_sys::general::{__kernel_pid_t, __kernel_timespec, TIMER_ABSTIME}; +#[cfg(target_pointer_width = "32")] +use { + core::convert::TryInto, core::ptr, linux_raw_sys::general::timespec as __kernel_old_timespec, +}; + +#[inline] +pub(crate) fn clock_nanosleep_relative( + id: ClockId, + req: &__kernel_timespec, +) -> NanosleepRelativeResult { + #[cfg(target_pointer_width = "32")] + unsafe { + let mut rem = MaybeUninit::<__kernel_timespec>::uninit(); + match ret(syscall!( + __NR_clock_nanosleep_time64, + id, + c_int(0), + by_ref(req), + &mut rem + )) + .or_else(|err| { + // See the comments in `rustix_clock_gettime_via_syscall` about + // emulation. + if err == io::Errno::NOSYS { + clock_nanosleep_relative_old(id, req, &mut rem) + } else { + Err(err) + } + }) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => NanosleepRelativeResult::Interrupted(rem.assume_init()), + Err(err) => NanosleepRelativeResult::Err(err), + } + } + #[cfg(target_pointer_width = "64")] + unsafe { + let mut rem = MaybeUninit::<__kernel_timespec>::uninit(); + match ret(syscall!( + __NR_clock_nanosleep, + id, + c_int(0), + by_ref(req), + &mut rem + )) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => NanosleepRelativeResult::Interrupted(rem.assume_init()), + Err(err) => NanosleepRelativeResult::Err(err), + } + } +} + +#[cfg(target_pointer_width = "32")] +unsafe fn clock_nanosleep_relative_old( + id: ClockId, + req: &__kernel_timespec, + rem: &mut MaybeUninit<__kernel_timespec>, +) -> io::Result<()> { + let old_req = __kernel_old_timespec { + tv_sec: req.tv_sec.try_into().map_err(|_| io::Errno::INVAL)?, + tv_nsec: req.tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + let mut old_rem = MaybeUninit::<__kernel_old_timespec>::uninit(); + ret(syscall!( + __NR_clock_nanosleep, + id, + c_int(0), + by_ref(&old_req), + &mut old_rem + ))?; + let old_rem = old_rem.assume_init(); + // TODO: With Rust 1.55, we can use MaybeUninit::write here. + ptr::write( + rem.as_mut_ptr(), + __kernel_timespec { + tv_sec: old_rem.tv_sec.into(), + tv_nsec: old_rem.tv_nsec.into(), + }, + ); + Ok(()) +} + +#[inline] +pub(crate) fn clock_nanosleep_absolute(id: ClockId, req: &__kernel_timespec) -> io::Result<()> { + #[cfg(target_pointer_width = "32")] + unsafe { + ret(syscall_readonly!( + __NR_clock_nanosleep_time64, + id, + c_uint(TIMER_ABSTIME), + by_ref(req), + zero() + )) + .or_else(|err| { + // See the comments in `rustix_clock_gettime_via_syscall` about + // emulation. + if err == io::Errno::NOSYS { + clock_nanosleep_absolute_old(id, req) + } else { + Err(err) + } + }) + } + #[cfg(target_pointer_width = "64")] + unsafe { + ret(syscall_readonly!( + __NR_clock_nanosleep, + id, + c_uint(TIMER_ABSTIME), + by_ref(req), + zero() + )) + } +} + +#[cfg(target_pointer_width = "32")] +unsafe fn clock_nanosleep_absolute_old(id: ClockId, req: &__kernel_timespec) -> io::Result<()> { + let old_req = __kernel_old_timespec { + tv_sec: req.tv_sec.try_into().map_err(|_| io::Errno::INVAL)?, + tv_nsec: req.tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + ret(syscall_readonly!( + __NR_clock_nanosleep, + id, + c_int(0), + by_ref(&old_req), + zero() + )) +} + +#[inline] +pub(crate) fn nanosleep(req: &__kernel_timespec) -> NanosleepRelativeResult { + #[cfg(target_pointer_width = "32")] + unsafe { + let mut rem = MaybeUninit::<__kernel_timespec>::uninit(); + match ret(syscall!( + __NR_clock_nanosleep_time64, + ClockId::Realtime, + c_int(0), + by_ref(req), + &mut rem + )) + .or_else(|err| { + // See the comments in `rustix_clock_gettime_via_syscall` about + // emulation. + if err == io::Errno::NOSYS { + nanosleep_old(req, &mut rem) + } else { + Err(err) + } + }) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => NanosleepRelativeResult::Interrupted(rem.assume_init()), + Err(err) => NanosleepRelativeResult::Err(err), + } + } + #[cfg(target_pointer_width = "64")] + unsafe { + let mut rem = MaybeUninit::<__kernel_timespec>::uninit(); + match ret(syscall!(__NR_nanosleep, by_ref(req), &mut rem)) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => NanosleepRelativeResult::Interrupted(rem.assume_init()), + Err(err) => NanosleepRelativeResult::Err(err), + } + } +} + +#[cfg(target_pointer_width = "32")] +unsafe fn nanosleep_old( + req: &__kernel_timespec, + rem: &mut MaybeUninit<__kernel_timespec>, +) -> io::Result<()> { + let old_req = __kernel_old_timespec { + tv_sec: req.tv_sec.try_into().map_err(|_| io::Errno::INVAL)?, + tv_nsec: req.tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + let mut old_rem = MaybeUninit::<__kernel_old_timespec>::uninit(); + ret(syscall!(__NR_nanosleep, by_ref(&old_req), &mut old_rem))?; + let old_rem = old_rem.assume_init(); + // TODO: With Rust 1.55, we can use MaybeUninit::write here. + ptr::write( + rem.as_mut_ptr(), + __kernel_timespec { + tv_sec: old_rem.tv_sec.into(), + tv_nsec: old_rem.tv_nsec.into(), + }, + ); + Ok(()) +} + +#[inline] +pub(crate) fn gettid() -> Pid { + unsafe { + let tid: i32 = ret_usize_infallible(syscall_readonly!(__NR_gettid)) as __kernel_pid_t; + debug_assert_ne!(tid, 0); + Pid::from_raw_nonzero(RawNonZeroPid::new_unchecked(tid as u32)) + } +} + +// TODO: This could be de-multiplexed. +#[inline] +pub(crate) unsafe fn futex( + uaddr: *mut u32, + op: FutexOperation, + flags: FutexFlags, + val: u32, + utime: *const Timespec, + uaddr2: *mut u32, + val3: u32, +) -> io::Result<usize> { + #[cfg(target_pointer_width = "32")] + { + ret_usize(syscall!( + __NR_futex_time64, + uaddr, + (op, flags), + c_uint(val), + utime, + uaddr2, + c_uint(val3) + )) + .or_else(|err| { + // See the comments in `rustix_clock_gettime_via_syscall` about + // emulation. + if err == io::Errno::NOSYS { + futex_old(uaddr, op, flags, val, utime, uaddr2, val3) + } else { + Err(err) + } + }) + } + #[cfg(target_pointer_width = "64")] + ret_usize(syscall!( + __NR_futex, + uaddr, + (op, flags), + c_uint(val), + utime, + uaddr2, + c_uint(val3) + )) +} + +#[cfg(target_pointer_width = "32")] +unsafe fn futex_old( + uaddr: *mut u32, + op: FutexOperation, + flags: FutexFlags, + val: u32, + utime: *const Timespec, + uaddr2: *mut u32, + val3: u32, +) -> io::Result<usize> { + let old_utime = __kernel_old_timespec { + tv_sec: (*utime).tv_sec.try_into().map_err(|_| io::Errno::INVAL)?, + tv_nsec: (*utime).tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + ret_usize(syscall!( + __NR_futex, + uaddr, + (op, flags), + c_uint(val), + by_ref(&old_utime), + uaddr2, + c_uint(val3) + )) +} |